Forced-draft hollow grate-bar or burner.



H. 0. DRSEY.

FORCED DRAFT HOLLOW GRATE BAR OR BURNER.

APPLICATION FILED NOV. 27. |915.

2 SHEETS-SHEET1.

Patented Nov. 21, 1916.

mal-m attorney H. 0. DORSEY..

FORCED DRAFT HOLLOW GRATE BAR OR BURNER..

APPLICATION FILED NOV. 27| 19.15.

Patented Nov. 21, I9I6.

2 SHEETSSHEET 2.

UNirEn sra as ACE.

HARRY O. DORSEY, 0F CHARLOTTE,` NORTH CAROLINA, ASSIGNOR TO WILLIAM C. GUNN, OF FORT SCOTT, KANSAS.

Specification of Letters Patent.

Patented Nov. 21, 1916.

Application filed November 27, 1915. Serial No. 63,793.

To all whom t may concern Y Be it known that I, HARRY O. DoRsEY, a citizen of the United States, residing at Charlotte, in the county of Mecklenburg and State of North Carolina, have invented new and useful Improvements in Forced-Draft Hollow Grate-Bars or Burners, of which the following is a specification.

This invention relates to certain new and useful improvements in hollow grate bars or burners for closed forced draft furnace beds or floors, and particularly to furnace beds or floors of that type wherein substantially Complete combustion of the available heat units of the fuel is designed to be obtained by'oxygenation resulting from the upward feed of currents of air through and between the fuel particles from the hollow grate bars, and wherein the clinkers, if any, remaining are raked out through the `fuel door and the ashes and other line refuse discharged through the hollow grate bars into the ash oit. 1 The primary object of the present invention is to provide hollow grate bars or burners for furnace grates of this character which, are provided with drop bottoms adapted to be freely opened and closed for natural or forced draft and to effect the discharge of the ashes and line refuse, and which obviates the objections to solid apertured bottoms with sliding or reciprocating closures or other like constructions which are liableto clog or bind or cause other troubles or annoyances.

A further object of the invention is to provide hollow grate bars of the character described composed of lower supporting sections and upper fuel carrying sections which are detachably connected, and which lower supporting sections are provided with means for connection with an air duct'for the supply of air under pressure and with hinged drop bottoms of the character described which are adapted to be opened and closed for natural draft or the free and easy discharge of ashes and other fine refuse.

A still further objectof the invention is to provide lever mechanism of novel construction for simultaneously and uniformly opening and closing one or more of the drop bottoms of the hollow grate bars in unison,

and whereby said drop bottoms may be easily and eonveniently spar-ated and l@maine tained in open or closed position for any predetermined period.

A still further object of the invention is to provide means for adjusting and regulating the throw of the actuating connections between the dropper bottoms and primary actuating elements so that proper adjustment may be made from time to time to compensate for expansion and contraction, warping' or wear of the parts, to insure the proper opening and closing movements of the dropper bottoms.

Vith these and other objects in View, the invention consists of the features of construction, combination and arrangement of parts hereinafter fully described and claimed, reference being had to the accompanying drawings in which Figure l is an irregular vertical longitudinal section through a furnace bed or grate embodying my invention. Fig. 2 is a vertical transverse section on the line 2 2 of Fig. l. Fig. 3 is a horizontal section through the main elements of the drop door actuating mechanism. Fig. et is a detail view of the weighted arm of the actuating shaft and the actuating lever.

The forced draft grate or burner embodyingmy invention comprises a series of any desired number of hollow grate lbars or burners 1, arranged in parallel relation to each other, and each consisting of an upper fuel carrying section 2 and a. lower supporting section Each grate bar or burner as thus constructed is in the nature of a substantially oblong rectangular hollow boX horizontally and longitudinally divided to form the sections 2 and 3 which may be detachably connected and supported in position in any preferred manner. As shown in the present instance each upper bar or burner section is formed of side walls Il, end walls 5 and a top wall G, the said top wall being provided with slits or apertures 7 for the upw-ard passage of air to and through the body of fuel, it being understood that the top walls of the hollow bars or burners constituting the grate form the fiat floor or fuel carrying surface of the grate which is closed or imperforate, and of a solid type against the downward passage of particles of fuel, with the exception of the slits or apertures' 7 for the upward flow of blasts off air.' 'Each lower bar or burner Y section is, like the upper section, also in the general form of a trough and comprises side walls 8. end walls 9 and a bottom wall 10. The said lower bar or burner section is open at the top and recessed to receive the base portion of the upper section and open at the bottom, and at intervals the interior of said lower bar or burner section is preferably provided with transverse segmental bracing ribs 11 to reinforce the same in an effective manner.

Each lower bar or g ate section 3 is provided with oifstanding lateral projections or shoulders 12 to rest upon suitable supports within the furnace casing, and the bottom opening of the section is normally closed by the wall 10. This wall 10 is hinged to form a drop bottom, and for this purpose is provided at each end in alinement with one of its side edges with trunnions 13 journaled in offset bearing portions 14- of bearing plates 15 disposed beneath flanges 1G adjacent to the o-pposite ends of the body of said grate section and secured thereto by bolts or other suitable fastenings 17. The drop bottoms 10 are adapted to be opened in a downward direction when it is desired to supply air under natural draft to the bed of fuel or to discharge from the hollow interiors or collecting chambers of the grate bars or burners the ashes and other line particles which may drop downward ther-cinto through the air blast apertures 7. By providing drop bottoms of this character, and means for operating the same of the character hereinafter described, the bottom openings of the lower grate bar section may be fully opened for the free and unimpeded upward iiow of air and also for the free and unimpeded passage of ashes and other refuse, thus obviating the objections to perforated bottoms with slides for controlling the same which are liable to become clogged in use or bind in operation, with obvious annoyances and objections.

The means for actuating' the dropper bottoms of any desired number of the grate or burner sections in series comprises a sliciing or reciprocating operating rod or bar 18 which is fitted to slide in supporting brackets 19 secured to and depending from the lower sections of certain of the hollow grate bars or burners and has clamped or otherwise adjustably secured thereto blocks 2O provided with wrist pins 21. The wrist pins of the respective blocks, which are equal in number to the grate bars, are respectively connected by links 22 with ears 23 on the hinged dropper bottoms of the grate bars, whereby on reverse sliding motions of the rod or bar 18 the dropper bottomsv 10 will be opened or closed, as indicated in dotted and full lines in Fig.` 2. One

kof thev blocksy is. also provided with va wrist pin 24 which is connected by a motion transmitting link or lever 25 with a crank arm 2G on an actuating` rock shaft 27 extending at right angles to the rod or bar 18. The rod or bar 18 may extend, as shown, tiansversely beneath the series of hollow grate bars or burners and of the furnace casing, and-the actuating rod or shaft 27 may extend longitudinally of the casing and outwardly through the front wall thereof, said shaft 27 being journaled at its forward end in the front wallof the casing and at its inner or rear end in a bearing plate 28 secured to a pair of spaced hanger' brackets 29 fastened to the lower section of one of the grates or burners. The construction and arrangement of the parts is thus such that the upper grate sections may be readily and conveniently removed for repairs or other purposes without disturbing the lower grate section, while the latter may be easily and conveniently detached when occasion requires for renewal or other purposes, the upper grate sections being removable without disturbingthe lower grate sections or the dropper bottom actuating mechanism. Where a limited number, say up to tive or six, grate sections are employed a single set of actuating devices of the character described will be sufficient, but where a greater number of grate bars are used they may be opposite positions beyond center to main v tain the dropper bottoms in either opened or closed position, as will be readily understood. l

In the o-peration ofthe grate it is very desirable to provide some means whereby the throw of the links 22, or pivoted'connections between the actuating shaft 18-and the dropper bottoms 10 may be varied from time to time, in order to compensate for variations in the relative positions of the grate bars and working parts due to warping, expansion and contraction, etc., particularly in the use of a new grate and until the elements of the grate haveset or finally assumed substantially permanent relative position-s. To this end, the blocks 2O are made adjustable upon the actuating shaft 18, so that said blocks may be shifted upon the said shaft as required to vary the angular relationship between the link 22 and dropper bottom 10, and consequently vary the degree of motion or throw of saidv link to secure opening and closing movements of the drpper betteln. Assnovvn particularly iso in Fig. 1, each block 20 is split or divided at its lower end through which the shaft 18 extends, thus forming jaws which are connected by a bolt and nut or other suitable means, allowing the edges to be relaxed for slidably adjusting the block on the shaft as required and then clamping or fixing it in adjusted position. By the adjustment of these blocks upon the shaft whenever required it will be evident that the connections may be always maintained in proper order to effect full opening and closing movement of the dropper bottoms, with resultant advantages and an increasing of efficiency of the grate.

It will be evident from the foregoing description that my invention provides a hollo-w grate bar or burner which is simple of construction, durable and efficient in use, and comparatively inexpensive of production, and a series of which may be employed to form a forced draft hollow grate or burner of the character set forth. It will also be seen that the dropper bottoms of the grates may be freely opened whenever it is desired to furnish a natural draft or discharge ashes and other fine refuse, inclosed whenever it is desired to employ a forced draft, the use of the dropper bottoms and actuating mechanism set forth obviating the obvious objections to perforated bottoms with sliding or other controlling valves which are liable to clog or bind and become inoperative or cause annoyance and inconvenience.

In practice, the hollow grate sections may be provided with air from a pump or blower suitably operated in any preferred manner. In the present instance I have shown the bottom section of each hollow grate or burner provided with a short fixed bottom portion 32 having an opening for communication with an air duct or pipe 33 leading from the source of air supply.

I claim 1. A grate of the character described including a series of hollow grate sections, each having a drop bottom, an actuating element extending transversely beneath the series of grate sections, connecting members cluding a series of parallel grate sections,

each provided with a gravity opening drop bottom, a reciprocating actuating device eX- tending transversely beneath said drop bottoms, connecting members, each adjustably mounted upon said actuating device, and links pivotally coupling the drop bottoms to different connecting members in vertical planes o-ut of alinement with each other so as 'to normally lie at an oblique angle to the drop bottoms and actuating device in the closed position of said drop bottoms.

3. A grate of the character described comprising a series of parallel grate sections, each provided with a hinged or pivoted gravity-opening drop bottom, an actuating device extending transversely beneath said grate sections, and a pivotal connection between each of said drop bottoms and said actuating device, each connection including adjusting means for independently varying the throw of the pivotal connections.

4. A grate of the character described including a series of parallel grate sections, each provided with a hinged or gravityopening` pivoted drop bottom, a reciprocating actuating rod disposed beneath the grate sections, blocks adjustably mounted upon the rod, and links pivotally coupling the respective dro-p bottoms separately to the different adjustable blocks, whereby the drop bottoms may be opened and closed in the reciprocating motions of the rod and the throw of the links independently varied.

In testimony whereof I afhx my signature in presence of two witnesses.

HARRY O. DORSEY.

Vitnesses W; L. ALEXANDER, JNO. B. ALEXANDER,

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

